Claim Missing Document
Check
Articles

Found 3 Documents
Search

Investigating the effects of corrosion parameters on the surface resistivity of transformer’s insulating paper using a two-level factorial design Azlan, Nur Farhana Mohd; Ghani, Sharin Ab; Khiar, Mohd Shahril Ahmad; Chairul, Imran Sutan; Din, Mohamad Nazri Mohamad
International Journal of Applied Power Engineering (IJAPE) Vol 13, No 2: June 2024
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijape.v13.i2.pp335-342

Abstract

The integrity of the insulation in oil-filled power transformers, shunt reactors, and high voltage bushings can be affected when copper dissolves in the insulating oil and then deposits onto the paper insulation. The presence of dissolved copper in the oil increases dielectric losses, while copper deposition significantly improves the conductivity of the paper insulation. Various factors, including temperature, oxygen, sulfur groups, passivators, and ageing time, have been found to contribute to the acceleration of corrosion activity in transformer insulating oils. Unfortunately, there is a lack of extensive research focused on systematically analysing and measuring the impact of corrosion-related factors on the dissolution of copper in transformer insulating oils and the deposition of copper onto solid insulation surfaces (Kraft paper). Therefore, this study aims to thoroughly examine the effects of corrosion factors on copper and sulfur deposition on Kraft paper insulation when it is submerged in transformer mineral oil (TMO). Using a two-level (2k) factorial design, we investigated three crucial factors: i) oil temperature, ii) elemental sulfur concentration, and iii) ageing time. It is worth mentioning that the results obtained from the two-level factorial design indicate that the surface resistivity is primarily affected by the temperature of the oil. This factor alone explains a significant 38.68% of the observed variation. In order to improve predictability, a regression model was created to estimate the surface resistivity of TMO-impregnated paper insulation. This model takes into account factors such as oil temperature, elemental sulfur concentration, and ageing time.
Illuminance study of lecture rooms and laboratories in an educational academic building based on the MS 1525 standard Zainal, Muhammad Asyraf; Ghani, Sharin Ab; Chairul, Imran Sutan; Khiar, Mohd Shahril Ahmad
International Journal of Advances in Applied Sciences Vol 14, No 1: March 2025
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijaas.v14.i1.pp193-199

Abstract

The lighting system is a crucial system in classrooms and other educational facilities such as laboratories and sports centers. Poor lighting conditions will affect the ability of the students to see clearly during classes and result in eye strain, fatigue, headache, and stress. Hence, this study aims to investigate the illuminance levels in four lecture rooms and six laboratories in the Faculty of Electrical Technology and Engineering, Universiti Teknikal Malaysia Melaka, Malaysia using DIALux evo 10.0 lighting design software. The illuminance levels determined from simulations were compared with the required illuminance levels for classrooms (300 lx) and laboratories (500 lx) stipulated in the Malaysian standards (MS) 1525-energy efficiency and use of renewable energy for non-residential buildings. Based on the results, the selected lecture rooms were overlit, whereas three of the laboratories were underlit. Suggestions were made to improve the illuminance levels of the lecture rooms and laboratories by changing the specifications of the lighting system or by making use of natural sunlight from the windows.
Sulphur corrosion in transformer insulating oils: its effects, detection methods, and mitigation strategies Zulkefli, Nur Izyan Husnina; Ghani, Sharin Ab; Khiar, Mohd Shahril Ahmad; Chairul, Imran Sutan; Rahim, Nor Hidayah; Azlan, Nur Farhana Mohd
International Journal of Advances in Applied Sciences Vol 14, No 3: September 2025
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijaas.v14.i3.pp784-792

Abstract

Oil-immersed transformers are subjected to electrical, thermal, and mechanical stresses over time, which inevitably affect the insulating oil and paper insulation. The presence of sulphur corrosion also degrades the insulating oil and paper insulation. Sulphur corrosion in insulating oils has been a prevalent problem for many years, as it culminates in the failure of oil-immersed transformers. The longevity of oil-immersed transformers is dependent on the integrity of the insulating oil and paper insulation, which can deteriorate owing to sulphur corrosion. The occurrence and accumulation of copper sulphide (Cu2S) can result in transformer malfunctions, which is a significant issue for transformer manufacturers and operators. This paper provides a concise overview of the effects of sulphur corrosion, its detection methods, as well as its mitigation strategies. It is believed that this paper will enhance the understanding of sulphur corrosion in insulating oils, provide the best practices for sulphur corrosion management, and serve as guidance on enhancing transformer reliability and performance.